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This Master thesis was carried out within the research project PONT3 (Anticipating failure propagation of ageing bridges through a cost-effective interdisciplinary approach, reference PID2021-124236OB-C32) funded by the Spanish Ministry of Science and Innovation and the State Research Agency, El projecte de recerca es centra en avaluar i caracteritzar ponts d'arc de maçoneria històrics de ferrocarril mitjançant mètodes de proves no destructives (NDT). L'objectiu és preservar i conservar aquestes estructures com a part del patrimoni històric. L'estudi es centra en un pont de maçoneria de principis del segle XX situat prop de Barcelona. El projecte comença amb una revisió del comportament estructural, les tècniques de construcció i els materials comúnment emprats en els ponts d'arc de maçoneria de ferrocarril. S'examinen diverses guies per avaluar els ponts d'arc de maçoneria per a l'avaluació del pont d'estudi. Una revisió bibliogràfica explora mètodes de proves no destructives i proves destructives menors per avaluar la condició general i les propietats mecàniques del pont. La investigació inclou un estudi detallat d'escriptori, investigant la informació històrica del pont, intervencions prèvies, construcció i geometria. A continuació, es realitza una investigació de camp i una campanya experimental que involucra la inspecció visual per identificar danys i avaluar la condició general del pont. Les dades recopilades permeten la creació d'un model geomètric 3D que mostra l'exterior i l'interior del pont. La campanya experimental utilitza proves no destructives com la velocitat de pols ultrasònica (UPV) i la termografia infraroja, així com proves destructives menors com el penetròmetre Windsor (PPT) i el martell de rebuig Schmidt (HRT). A més, es realitzen proves destructives al laboratori per determinar la resistència a compressió de la maçoneria. En general, el projecte té com a objectiu promoure l'ús de tècniques no destructives en la caracterització d'estructures de maçoneria històriques, contribuint a la base de dades experimentals i a la preservació d'aquests importants actius patrimonials., El proyecto de investigación se centra en evaluar y caracterizar puentes de arco de mampostería históricos de ferrocarril mediante métodos de pruebas no destructivas (NDT). El objetivo es preservar y conservar estas estructuras como parte del patrimonio histórico. El estudio se centra en un puente de mampostería de principios del siglo XX ubicado cerca de Barcelona. El proyecto comienza con una revisión del comportamiento estructural, las técnicas de construcción y los materiales comúnmente utilizados en puentes de arco de mampostería de ferrocarril. Se examinan varias guías para evaluar puentes de arco de mampostería para evaluar el puente de estudio. Una revisión bibliográfica explora métodos de pruebas no destructivas y pruebas destructivas menores para evaluar la condición general y las propiedades mecánicas del puente. La investigación incluye un estudio detallado de escritorio, investigando la información histórica del puente, intervenciones previas, construcción y geometría. A continuación, se llevó a cabo una investigación de campo y una campaña experimental que involucra la inspección visual para identificar daños y evaluar la condición general del puente. Los datos recopilados permitieron la creación de un modelo geométrico 3D indicando el exterior e interior del puente. La campaña experimental utiliza pruebas no destructivas como la velocidad de pulso ultrasónico (UPV) y la termografía infrarroja, así como pruebas destructivas menores como el penetrómetro Windsor (PPT) y el martillo de rebote Schmidt (HRT). Además, se realizan pruebas destructivas en el laboratorio para determinar la resistencia a compresión del ladrillo. En general, el proyecto tiene como objetivo promover el uso de técnicas no destructivas en la caracterización de estructuras de mampostería históricas, contribuyendo a la base de datos experimentales y a la preservación de estos importantes activos patrimoniales., The research project focuses on assessing and characterizing historical masonry railway arch bridges through non-destructive testing (NDT) methods. The objective is to preserve and conserve these structures as part of the historical heritage. The study centers around an early 20th-century masonry bridge located near Barcelona. The project begins with a review of the structural behavior, construction techniques, and materials commonly employed in railway masonry arch bridges. Various guidelines for assessing masonry arch bridges are examined to evaluate the case study bridge. A literature review explores non-destructive and minor destructive test methods for assessing the bridge's overall condition and mechanical properties. The research includes a thorough desk study, investigating the bridge's historical information, previous interventions, construction, and geometry. A site investigation and experimental campaign follow, involving visual inspection to identify damages and assess the overall condition. The gathered data enables the creation of a 3D geometrical model showcasing the bridge's exterior and interior. The experimental campaign employs non-destructive tests such as Ultrasonic Pulse Velocity (UPV) and Infrared Thermography, as well as minor destructive tests like the Windsor Pin Penetrometer (PPT) and Schmidt Hammer Rebound (HRT). Additionally, destructive tests are conducted in the laboratory to determine compressive strength. Overall, the project aims to promote the use of non-destructive techniques in characterizing historical masonry structures, contributing to the field's experimental database and the preservation of these important heritage assets.

Statistics has shown that Malaysia receives high frequency of landslide while Cameron Highlands (CH) is one of the landslide prone hotspots. Previous studies have been conducted on landslide assessment but most research focused on urbanised populated area and limited study was conducted in forested mountainous area of CH. Most of the Malaysian show insufficient knowledge and low awareness regard landslide issue even though landslide case is not rare in this country. Besides, Digital Terrain Model (DTM) developed by radiogrammetry technology tends to produce spatial data with high precision. However, application of DTM in terrain assessment of mountainous forest was said to be challenging due to its complex terrain structure. This study aimed to demonstrate method to map terrain morphological characteristics and establish a terrain sensitivity map in landslide prone area of CH. Moreover, this study also aimed to analyse the landslide density in forested and non forested area of CH and evaluate the accuracy of DTM application in terrain assessment of mountainous forest. DTM of CH was applied to generate the terrain parameters which are elevation, slope gradient, aspect, Length-slope Factor (LS Factor) and Topography Wetness Index (TWI). All parameters were integrated, and a terrain sensitivity map was simulated by using weighted overlay analysis. Field assessment was conducted to collect landslide coordinate as data for landslide density measurement and DTM accuracy assessment. Result shows that 35.28% of slopes which are scatterly distributed in CH are classified as high sensitive area with landslide density of 2.18unit/km. Ringlet Forest Reserve recorded the highest frequency of landslide occurrence in forested area with 9.09unit/km, and Kuala Terla area recorded 4.01unit/km in non-forested area. Map comparison with field verification suggested that the DTM based Terrain Sensitivity Map generated obtained accuracy of 79.25%. Results presented provide a significant c

Statistics has shown that Malaysia receives high frequency of landslide while Cameron Highlands (CH) is one of the landslide prone hotspots. Previous studies have been conducted on landslide assessment but most research focused on urbanised populated area and limited study was conducted in forested mountainous area of CH. Most of the Malaysian show insufficient knowledge and low awareness regard landslide issue even though landslide case is not rare in this country. Besides, Digital Terrain Model (DTM) developed by radiogrammetry technology tends to produce spatial data with high precision. However, application of DTM in terrain assessment of mountainous forest was said to be challenging due to its complex terrain structure. This study aimed to demonstrate method to map terrain morphological characteristics and establish a terrain sensitivity map in landslide prone area of CH. Moreover, this study also aimed to analyse the landslide density in forested and non forested area of CH and evaluate the accuracy of DTM application in terrain assessment of mountainous forest. DTM of CH was applied to generate the terrain parameters which are elevation, slope gradient, aspect, Length-slope Factor (LS Factor) and Topography Wetness Index (TWI). All parameters were integrated, and a terrain sensitivity map was simulated by using weighted overlay analysis. Field assessment was conducted to collect landslide coordinate as data for landslide density measurement and DTM accuracy assessment. Result shows that 35.28% of slopes which are scatterly distributed in CH are classified as high sensitive area with landslide density of 2.18unit/km. Ringlet Forest Reserve recorded the highest frequency of landslide occurrence in forested area with 9.09unit/km, and Kuala Terla area recorded 4.01unit/km in non-forested area. Map comparison with field verification suggested that the DTM based Terrain Sensitivity Map generated obtained accuracy of 79.25%. Results presented provide a significant c

Local wind fields that account for topographic interaction are a key element for any wildfire spread simulator. Currently available tools to generate near-surface winds with acceptable accuracy do not meet the tight time constraints required for data-driven applications. This article presents the specific problem of data-driven wildfire spread simulation (with a strategy based on using observed data to improve results), for which wind diagnostic models must be run iteratively during an optimisation loop. An interpolation framework is proposed as a feasible alternative to keep a positive lead time while minimising the loss of accuracy. The proposed methodology was compared with the WindNinja solver in eight different topographic scenarios with multiple resolutions and reference – pre-run– wind map sets. Results showed a major reduction in computation time (~100 times once the reference fields are available) with average deviations of 3% in wind speed and 3° in direction. This indicates that high-resolution wind fields can be interpolated from a finite set of base maps previously computed. Finally, wildfire spread simulations using original and interpolated maps were compared showing minimal deviations in the fire shape evolution. This methodology may have an important effect on data assimilation frameworks and probabilistic risk assessment where high-resolution wind fields must be computed for multiple weather scenarios., Peer Reviewed, Postprint (author's final draft)

This study evaluates the data assimilation capabilities of Three Dimensional Multiquadric Interpolation (3DMQ) and the MM5 model when incorporating mesoscale observations from the United States Air Force Academy (USAFA) High Wind Alert system (HWAS). These mesoscale observations are incorporated into a triple nested (12, 4, and 1.33 km) high resolution model simulation and evaluated for their impact upon analyzed and forecasted wind values at USAFA during a severe downslope wind event that occurred on 6 March 2004. This evaluation is the first step in developing future forecasting and analysis tools for use by the military in various operations in complex terrain. The development of deployable automated tactical weather sensors in forward deployed locations requires an evaluation of the impact and usefulness these sensors would have on analysis forecast tools and mesoscale Numerical Weather Prediction (NWP) models. The juxtaposition of the HWAS network in complex terrain and the aviation training operations at USAFA provides an ideal set of data, mission and location for testing and evaluating a high resolution nested grid mesoscale NWP model. This study shows that incorporating HWAS observations into the 3DMQ data assimilation process has a significant impact upon verification of analyzed wind fields with the biggest impact occurring at the 1.33 km grid scale. Using these analyzed fields as initial conditions for MM5 model simulations, this study shows the ability of the 1.33 km model forecast wind fields to verify significantly better than either the 4 or 12 km through 18, 24, and 30 hour forecasts. Additionally, this study shows the limited, yet discernable impact HWAS observations have upon forecasted winds in the first several hours of MM5 model runs during a severe downslope wind event at USAFA.

This study evaluates the data assimilation capabilities of Three Dimensional Multiquadric Interpolation (3DMQ) and the MM5 model when incorporating mesoscale observations from the United States Air Force Academy (USAFA) High Wind Alert system (HWAS). These mesoscale observations are incorporated into a triple nested (12, 4, and 1.33 km) high resolution model simulation and evaluated for their impact upon analyzed and forecasted wind values at USAFA during a severe downslope wind event that occurred on 6 March 2004. This evaluation is the first step in developing future forecasting and analysis tools for use by the military in various operations in complex terrain. The development of deployable automated tactical weather sensors in forward deployed locations requires an evaluation of the impact and usefulness these sensors would have on analysis forecast tools and mesoscale Numerical Weather Prediction (NWP) models. The juxtaposition of the HWAS network in complex terrain and the aviation training operations at USAFA provides an ideal set of data, mission and location for testing and evaluating a high resolution nested grid mesoscale NWP model. This study shows that incorporating HWAS observations into the 3DMQ data assimilation process has a significant impact upon verification of analyzed wind fields with the biggest impact occurring at the 1.33 km grid scale. Using these analyzed fields as initial conditions for MM5 model simulations, this study shows the ability of the 1.33 km model forecast wind fields to verify significantly better than either the 4 or 12 km through 18, 24, and 30 hour forecasts. Additionally, this study shows the limited, yet discernable impact HWAS observations have upon forecasted winds in the first several hours of MM5 model runs during a severe downslope wind event at USAFA., http://archive.org/details/evaluationofhigh109453595, US Air Force (USAF) author., Approved for public release; distribution is unlimited.

Computer generated 3D graphics have been commonplace in computing since the early 1990's. However, most 3D scenes have focused on relatively small areas such as rooms or buildings. Rendering large scale landscapes based on 3D geometry generally did not occur because the scenes generated tended to use up too much system memory and overburden 3D graphics cards with too many polygons. However, there are applications where the terrain is critical and needs to be rendered properly such as cartography and military simulation. This thesis is focused on methods of rendering terrain for such applications. The data used to build terrain geometry typically comes from elevation postings taken from surveys of the terrain. This thesis does not focus on collecting this data nor does it compare various sources of terrain data. Instead, this thesis is about taking elevation data, producing a rendered 3D scene, and placing objects within the scene relative to the terrain. Having these capabilities makes many military and cartographic applications possible. Some military applications include displaying the results of computer simulations in 3D, planning operations using a 3D landscape, and rehearsing operations in 3D. The military does have some tools that can be used today for these actions, but the tools are typically proprietary and expensive. This thesis is focused on using and extending open source tools for 3D terrain rendering. The result is tools that can be freely used, studied, and expanded by anyone without licensing costs., http://archive.org/details/renderinglargesc109456191, Captain, United State Army, Approved for public release; distribution is unlimited.

The article detail the systematic process for transformation the 2D representation to 3D representation, likewise the systematic process for gather up of data, and the considerations and instrumentation necessary for this action., Peer Reviewed

This pamphlet describes the method employed by this organization in the rapid production of light weight terrain models.